animation problem

[Anonymous]

Hello. I'm new here and fairly new to Maxscript.

I have been working on an importer script to import 3 different files into max: a mesh file, a bone file, and an animation file.

I've successfully completed the first two (I think) but I have run into problems getting the animation right.

f = getOpenFileName caption: "Import Animation" types: "Animation (*.ani)|*.ani"
 
 ReadANI f &Animation
 
 For BoneID = 1 To Animation.BoneData.names.Count Do
 (
 obj = getnodebyname Animation.BoneData.names
 if obj != undefined Then
 (
 If Animation.BoneTM == undefined Then
 (
 tm = Animation.BoneTM
 
 For FrameID = 1 To Animation.FrameCount Do
 (
 rot = Animation.BoneFrame.Rotation
 trans = Animation.BoneFrame.Translation
 
 
 animate on
 (
 at time FrameID (obj.pos = trans; obj.rotation = rot)
 )
 )
 )
 else
 (
 if tm != undefined Then obj.transform = tm
 )
 )
 )

as you can see the problem lies within the animate on code block. I have a series of positions and rotations for each bone in each frame. Given that the bones have parents or are a child of parents. The model has a skin modifier with the bones added in. I had to do that manually as I am still working on it.

My question is am I doing something wrong with the animation because it gives weird results. I have a picture to illustrate the problem better

[Anonymous]

I can't tell precisely what is wrong here unless I see how you are storing your rotation and translation, I only see how you are applying it. From what I can tell it may not work out as easily as you have it written. I've found the best way to store animation is capturing each keyframe for position and rotation individually then storing the transforms for all the keys. However, just storing the world transform may not be sufficient. If I know the bone has a parent and will continue to have a parent I will store an offset matrix of that transform in parent space. This will generally get exactly what I want. Additionally, after all the transforms are set you can go back through and remove the specific translation, rotation, scale keys that may have been created, where you don't want them, as a result of setting the transforms. That requires another step but is really only a cleanup.

Pseudo Code:

fn get_bone_animation bone = 
(
 -- get each translation keyframe
 anim_keys = #()
 for i in bone.controller.position.controller.keys do append anim_keys i.time

 -- get each rotation keyframe
 for i in bone.controller.rotation.controller.keys do appendifunique anim_keys i.time

 -- store the bone transform for every frame there is a key
 anim_transforms = #()
 for i in anim_keys do (
  at time i (
    if bone.parent == undefined then (
      -- world space transform
      append anim_transforms bone.transform
    ) else (
      -- parent space transform
      append anim_transforms (bone.transform * inverse bone.parent.transform)      
    )
  )
 )
 return anim_transforms
)

fn set_bone_animation bone transforms =
(
  for i in transforms do (
    with animate on (
      -- you will have to capture your time somewhere probably in your structure
      at time (
        -- apply transforms
        if bone.parent == undefined then (
           bone.transform = transforms
        ) else (
           bone.transform = (transforms * bone.parent.transform)
        )
      )
    )
  )
)

[Anonymous]

I will try to incorporate what you said into my script. In the meantime here is the functions for reading and storing the animation file. I want to let everyone know that this format is based on the ASE format but with some differences. People familiar with ASE will spot the similarities.

Function ReadCHR FileName &BoneData &Version =
 (
 If FileName == Undefined Then Return False
 BoneData = ClsBoneData()

 Local FileHandle = 0
 Local I = 0
 
 FileHandle = FOpen FileName "rbS"

 Version = ReadLong FileHandle #Unsigned
 If Version < 4 Then
 MessageBox "Invalid Version, attempting to continue anyway."
 
 BoneData.ID = ReadLong FileHandle #Unsigned
 BoneData.BoneCount = ReadLong FileHandle #Unsigned
 
 CreateArray &BoneData.Names BoneData.BoneCount
 CreateArray &BoneData.TM BoneData.BoneCount
 CreateArray &BoneData.InverseTM BoneData.BoneCount
 CreateArray &BoneData.LocalTM BoneData.BoneCount
 CreateArray &BoneData.Parents BoneData.BoneCount
 
 For I = 1 To BoneData.BoneCount Do
 (
 FSeek FileHandle 4 #Seek_Cur --Bone Name Len
 BoneData.Names  = ReadString FileHandle
 BoneData.TM = ReadMatrix FileHandle
 BoneData.InverseTM = ReadMatrix FileHandle
 BoneData.LocalTM = ReadMatrix FileHandle
 BoneData.Parents = (ReadLong FileHandle #Signed) + 1
 
 If (FindString BoneData.Names "L ForeArm") != Undefined Then BoneData.LeftArmIndex = I
 Else If (FindString BoneData.Names "R ForeArm") != Undefined Then BoneData.RightArmIndex = I
 Else If (FindString BoneData.Names "L Hand") != Undefined Then BoneData.LeftHandIndex = I
 Else If (FindString BoneData.Names "R Hand") != Undefined Then BoneData.RightHandIndex = I
 )
 
 BoneData.SendVS = ReadLong FileHandle #Unsigned
 
 BoneData.LocalRH = ReadMatrix FileHandle
 BoneData.LocalShield = ReadMatrix FileHandle
 BoneData.LocalKnuckle = ReadMatrix FileHandle
 
 If Version == 5 Then
 (
 CreateArray &BoneData.Events 4
 CreateArray &BoneData.EventParents 4
 For I = 1 To 4 Do BoneData.Events = ReadVector3 FileHandle
 For I = 1 To 4 Do BoneData.EventParents = ((ReadLong FileHandle #Signed) + 1)
 )
 If Version >= 6 Then
 (
 CreateArray &BoneData.Events 8
 CreateArray &BoneData.EventParents 8
 For I = 1 To 8 Do BoneData.Events = ReadVector3 FileHandle
 For I = 1 To 8 Do BoneData.EventParents = ((ReadLong FileHandle #Signed) + 1)
 )
 If Version == 7 Then
 (
 BoneData.LocalLH = ReadMatrix FileHandle
 )
 FClose FileHandle
 )
 
 Function ReadANI FileName &ANI =
 (
 If FileName == Undefined Then Return False
 Ani = ClsAnimationData()

 Local FileHandle = 0
 Local Version = 0
 Local FrameCount = 0
 Local BoneCount = 0
 Local PathPresent = 0
 Local EventCount = 0
 Local I = 0
 
 ANI.Name = GetFilenameFile FileName

 FileHandle = FOpen FileName "rbS"

 Version = ReadLong FileHandle #Unsigned
 If Version != 10 Then
 MessageBox "Invalid Version, attempting to continue anyway."

 ANI.ID = ReadLong FileHandle #Unsigned
 ANI.PerSLERP = ReadFloat FileHandle
 FSeek FileHandle 32 #Seek_Cur
 BoneCount = ReadLong FileHandle #Unsigned
 FrameCount = ReadLong FileHandle #Unsigned
 ANI.FrameCount = FrameCount
 PathPresent = ReadLong FileHandle #Unsigned
 If PathPresent != 0 Then FSeek FileHandle (12 * FrameCount) #Seek_Cur
 ReadTM FileHandle &ANI BoneCount FrameCount
 CreateArray &ANI.Attribs FrameCount
 For I = 1 To FrameCount Do
 (
 ANI.Attribs = ClsAttributes()
 ANI.Attribs.Flags = ReadLong FileHandle #Unsigned
 ANI.Attribs.SoundID = ReadLong FileHandle #Unsigned
 ANI.Attribs.Frame = ReadFloat FileHandle
 )
 EventCount = ReadLong FileHandle #Unsigned
 If EventCount != 0 Then
 (
 CreateArray &ANI.Events EventCount
 For I = 1 To EventCount Do ANI.Events = ReadVector3 FileHandle
 )
 )

Function ReadTM FileHandle &AnimationData TotalBones TotalFrames =
 (
 Local NameLength = 0
 Local PoolSize = 0
 Local AnimationPresent = 0
 Local I = 0
 Local J = 0

 AnimationData.BoneData = ClsBoneData()
 AnimationData.FrameCount = TotalFrames
 AnimationData.BoneData.BoneCount = TotalBones
 CreateArray &AnimationData.BoneData.Names TotalBones
 CreateArray &AnimationData.BoneData.TM TotalBones
 CreateArray &AnimationData.BoneData.InverseTM TotalBones
 CreateArray &AnimationData.BoneData.LocalTM TotalBones
 CreateArray &AnimationData.BoneData.Parents TotalBones
 For I = 1 To TotalBones Do
 (
 FSeek FileHandle 4 #Seek_Cur
 AnimationData.BoneData.Names = ReadString FileHandle
 AnimationData.BoneData.InverseTM = ReadMatrix FileHandle
 AnimationData.BoneData.LocalTM = ReadMatrix FileHandle
 AnimationData.BoneData.Parents = ((ReadLong FileHandle #Signed) + 1)
 --Generate TM matrix to fill out the whole structure
 AnimationData.BoneData.TM = Inverse AnimationData.BoneData.InverseTM
 )

 FSeek FileHandle 4 #Seek_Cur --Skip PoolSize
 CreateArray &AnimationData.BoneTM TotalBones
 CreateArray &AnimationData.BoneFrame TotalBones
 For I = 1 To TotalBones Do
 (
 AnimationPresent = ReadLong FileHandle #Unsigned
 If AnimationPresent != 1 Then
 (
 AnimationData.BoneTM = ReadMatrix FileHandle
 )
 Else
 (
 CreateArray &AnimationData.BoneFrame TotalFrames
 For J = 1 To TotalFrames Do
 (
 AnimationData.BoneFrame = ClsFrame()
 AnimationData.BoneFrame.Rotation = ReadQuaternion FileHandle
 AnimationData.BoneFrame.Translation = ReadVector3 FileHandle
 )
 )
 )
 )
 
 Function ReadTMAni FileHandle &GeometryObject FrameCount =
 (
 Local FramePresent = ReadLong FileHandle #Unsigned
 Local I = 0
 If FramePresent != 0 Then
 (
 CreateArray &GeometryObject.StaticFrames FrameCount
 For I = 1 To FrameCount Do
 (
 GeometryObject.StaticFrames = ClsFrame()
 GeometryObject.StaticFrames.Rotation = ReadQuaternion FileHandle
 GeometryObject.StaticFrames.Translation = ReadVector3 FileHandle
 )
 )
 )

[Anonymous]

still no luck getting animation to work. would love to see if anyone has a solution to this problem.

[paulneale]

With it all left justified it is very hard to read it. I'm still not 100% clear on what the issues you are see are? You say the rotations are not correct? What space are they being stored and applied in?

[Anonymous]

Each bone has 3 matrices: TM, InverseTM, and LocalTM. My guess is they already calculated the Inverse Trans Matrix instead of doing the work by hand.

Each animation frame checks if there is a Bone Transform for each bone. If there isn't one, the it uses the Rotation quat and Translation stored therein.

My problem is that I do not know how to rotate and translate each bone. I don't know if its local space or parent space. I do know that a bone that has a parent bone is rotated in parent space but that really all I know.

I've tried a lot of things and this is pretty close but some bones are behaving wildly.

For BoneID = 1 To Animation.BoneData.names.Count Do (
 obj = getnodebyname Animation.BoneData.names
 if obj != undefined Then
 (
 if Animation.BoneTM == undefined Then
 (
 For FrameID = 1 To Animation.FrameCount Do (
 Frame = Animation.BoneFrame
 if Frame == undefined Then ( return 0 ) else
 (
 CurFrame = Frame
 --curBoneFrame = Animation.BoneFrame
 if (FrameID + 1) >= Animation.FrameCount Then ( nextBoneFrame = Animation.BoneFrame ) else ( nextBoneFrame = Animation.BoneFrame)

 -- Get QuatSlerp
 quatSlerp = slerp CurFrame.Rotation nextBoneFrame.Rotation Animation.PerSLERP
 -- GetVecLerp
 vecLerp = lerp CurFrame.Translation nextBoneFrame.Translation 1
 -- Make new Rotation Matrix
 mQ = quatSlerp as matrix3
 -- Make new Translation
 
 local mTemp = mQ
 mTemp.row4 = vecLerp
 
 format "Frame:% MatTemp:%\n" FrameID mTemp
 
 if FrameID == Animation.FrameCount Then FrameID = Animation.FrameCount else FrameID += 1
 
 if obj.parent != 0 Then (
 
 with animate on (
 at time FrameID 
 (
 in coordsys parent obj.rotation = mQ;
 in coordsys parent obj.pos = vecLerp
 )
 )
 ) else (
 with animate on (
 at time FrameID
 (
 in coordsys local obj.rotation.x_rotation = mQ;
 in coordsys local obj.pos = vecLerp
 )
 )
 )
 )
 )
 )
 )
 )